Design and characterization of a tunable patch antenna loaded with capacitive MEMS switch using CSRRs structure on the patch

Abstract

In this paper, the design and characterization of a tunable patch antenna loaded with complementary split ring resonators (CSRRs) on the patch have been realized. To achieve tunable resonant frequency, bandwidth and radiation pattern, the antenna is further loaded with coplanar waveguide (CPW) on which Microelectromechanical System (MEMS) capacitive switches are placed periodically. The tunable property is achieved, when the switches moves from up state with the capacitive gap 1.5μm to down state having capacitive gap of 1μm. A parametric analysis has been presented to check the sensitivity of the antenna in terms of S11 parameter by varying different parameters of the MEMS switches and CSRRs. This work, strives to improve the degree of reconfigurability with increase in the number of switches. The value of actuation voltage to move switch from up to down state is 10.4V, which is very low over the other design. The switches exhibit fundamental frequency 14.6kHz, switching time 28.59μs, and capacitance ratio 15.27. Simulation has been carried out in Ansoft HFSS v. 13 and the distinct characterization property of the tunable antenna is shown through simulation.